A conventional book binding apparatus carrying out perfect binding is disclosed in Patent Document 1.
The book binding apparatus disclosed in Patent Document 1 has a clamper movable along a predetermined path while gripping a book block in a standing state, a series of processing units (a milling unit, a glue application unit and a cover attachment unit) arranged along the path to carry out perfect binding, and a book block supplying unit arranged at a book block supply position upstream of the series of processing units on the path to supply the book block to the clamper.
The clamper includes a pair of clamp plates movable between an open position in which the pair of clamp plates receives the book block therebetween and a closed position in which the pair of clamp plates grips the book block therebetween. When the clamper is arranged at the book block supply position, the book block is supplied from the book block supplying unit to a gap between the pair of clamp plates which takes the open position, and the pair of clamp plates takes the closed position, thereafter, the book block is bounded while the clamper leaving the book block supply position and passing through the series of processing units.
The book block supplying unit is arranged downstream of a sheet stacking unit. The sheet stacking unit sequentially and horizontally stacks sheets discharged from a printer or a copier to form a book block.
The book block supplying unit comprises a conveying section which receives the book block from the sheet stacking unit and conveys the book block horizontally, and a pivoting section which receives the book block from the conveying section and pivots the book block through an angle of 90 degrees to set the book block in a standing state at a book block supply position.
The conveying section of the book block supplying unit comprises a horizontal transfer table provided with slots extending in a direction of conveying the book block, a pair of rollers spaced from each other in the conveying direction under the transfer table and extended perpendicular to the conveying direction, an endless belt extended between the pair of rollers, a drive mechanism rotating the pair of rollers, and a plurality of dogs fixed to the endless belt to project upward from the slots of the transfer table.
Thus the dogs are moved in the conveying direction on the transfer table by rotation of the endless belt and thereby, the book block in a state of lying is pressed by the dog at a fore edge thereof so that the book block is horizontally conveyed toward the pivoting section.
The pivoting section of the book block supplying unit comprises a pair of jaws movable between an open position in which the pair of jaws receives the book block therebetween and a closed position in which the pair of jaws grips the book block therebetween, an abutment arranged at a right angle to the pair of jaws and opposite to a gap between the jaws, and a mechanism rotating the pair of jaws and the abutment in an integrated manner around a horizontal axis which is positioned below the book block supply position and extended at a right angle to the conveying direction of the conveying section between a horizontal position (in which the pair of jaws horizontally extends) and a vertical position rotated 90 degrees from the horizontal position.
Thus when the pair of jaws and abutment take the horizontal position and the pair of jaws takes the open position, the book block is inserted into a gap between the pair of jaws by the conveying section until the book block abuts with the abutment at a spine thereof, and then the pair of jaws takes the closed position and the pair of jaws as well as the abutment take the vertical position, whereby the book block is set at the book block supply position.
Next, the clamper enters and stops at the book block supply position while keeping the pair of clamp plates thereof in the open position. At this time a portion of the book block between the pair of jaws and abutment is inserted into the gap of the pair of clamp plates.
After that, the pair of clamp plates takes the closed position and the pair of jaws takes the open position. Thereby the supply of the book block from the book block supplying unit to the pair of clamp plates of the clamper is completed, and the clamper leaves the book block supply position while gripping the book block and the pair of jaws and abutment of the book block supplying unit take the horizontal position.
However, according to this configuration, the book block formed by the sheet stacking unit is conveyed in a lying state by the conveying unit and rotated 90 degrees to a standing state by the pivoting unit, which leads to the following problems: The book block supplying unit takes a long time to supply the book block to the clamper and thereby the production efficiency decreases, and the book block supplying unit becomes larger and complicated and thereby the downsizing of the unit is hindered and the manufacturing cost increases